Some computing devices (e.g., mobile phones, tablet computers, etc.) provide graphical keyboards, handwriting recognition systems, speech-to-text systems, and other types of user interfaces (“UIs”) for composing electronic documents and messages. Such user interfaces may provide ways for a user to input text as well as some other limited forms of media content (e.g., emotion icons or so-called “emoticons”, graphical images, voice input, and other types of media content) interspersed within the text of the documents or messages.